1. Technical Field
The present invention relates to an apparatus and process for detecting an abnormality in a recorded signal, and, more particularly, to apparatus and processes for detecting abnormalities in recorded signals during the recording of the signal onto a recording medium.
2. Related Art
Generally, a digital magnetic recorder/player such as a digital video cassette (DVC), or the like, records and reproduces a digital signal, with advantages of higher quality of image and sound over an analog type signal, and also an easier editing process. The digital magnetic recorder/player generally uses a magnetic tape as a recording medium for storing the digital data of image and sound. Heads are formed on a rotary head drum of the recorder/player to record and reproduce signals on and from the magnetic tape.
During the use of the recorder/player, possibility is high that foreign substances are transferred from the magnetic tape to the head. Another high possibility is that foreign substances, floating in air, can be attached to the surface of the head. In the event that foreign substances are attached to the surface of the head, malfunction occurs in recording or reproducing process, causing undesired and abnormal signal recording or reproducing. In order to eliminate the foreign substances, a foreign substance cleaning tape is used, and sometimes, a user eliminates the foreign substances manually.
The source of abnormal recording/reproducing comes not only from the presence of foreign substances on the surface of the head, but also from problems associated with the head itself, or the errors of peripheral circuits which supply recorded signal to the head. Whether the abnormal signal recording is caused by the presence of foreign substances on the head or from problems associated with the head or other devices, the overriding difficulty is that the user does not immediately learn about the presence of the abnormality because the user is not provided with any way to either detect the occurrence of the abnormality or to identify or otherwise locate the cause of the abnormality. Although a user could consider the quality of image and sound for determining abnormal signal recording through the user""s anatomical audio and visual senses during reproducing process, during the recording process, the user is not able to determine if the abnormal signal is being recorded or if the information that is being recording is not being recorded at all. As a result, the user usually keeps recording for a long period of time, only to find that all of the user""s labors were a waste of time and effort. I have noticed that recording operations that produce errors or abnormalities can be extremely inconvenient; often the recording efforts can not be recreated once the defective equipment has been repaired or replaced. Efforts have been made to improve recording technologies.
Exemplars of recent efforts in the art include U.S. Pat. No. 6,141,486 for METHODS AND APPARATUS FOR RECORDING DIGITAL DATA INCLUDING SYNC BLOCK AND TRACK NUMBER INFORMATION FOR USE DURING TRICK PLAY OPERATION issued to Lane et at., U.S. Pat. No. 4,849,979 for FAULT TOLERANT COMPUTER ARCHITECTURE issued to Maccianti et al, U.S. Pat. No. 6,141,164 for DATA RECORDING/REPRODUCING APPARATUS EMPLOYING READ-AFTER-WRITE SYSTEM issued to Ishibashi et al, U.S. Pat. No. 6,134,384 for DIGITAL SIGNAL RECORDING/REPRODUCING APPARATUS AND RECORDING METHOD issued to Okamoto et al., U.S. Pat. No. 5,291,342 for MULTIFUNCTIONAL CONTROL TYPE VIDEO HEAD SELECTING DEVICE AND METHOD THEREOF issued to Kim, and U.S. Pat. No. 6,163,421 for AZIMUTH MAGNETIC RECORDING AND REPRODUCING APPARATUS AND METHOD EMPLOYING WAVEFORM EQUALIZATION issued to Shinpuku et al. While these recent efforts provide advantages, I note that they fail to adequately provide an apparatus and method for efficiently and conveniently detecting abnormalities in recorded signals.
It is therefore, one object of the present invention to provide an improved process and apparatus for recording information.
It is another object to provide a process and apparatus that enables a user to promptly detect the presence of abnormalities in information recorded onto a record medium.
It is still another object to provide a process and apparatus that enables a user to promptly detect the occurrence of abnormalities during the recording of information onto a record medium.
It is yet another object to provide an apparatus and process for detecting an abnormality of recorded signal of a digital magnetic recorder/player during a process of recording a signal on a magnetic tape, which is occurred when recording is abnormally performed by the presence of foreign substances on the head or by other problem sources.
These and other objects may be attained with an apparatus for detecting an abnormality of a recorded signal of a digital magnetic recorder/player according to the present invention, including a plurality of heads for recording/reproducing a signal on/from a magnetic tape, a control portion for controlling the heads in such a manner that the signal, recorded by at least one head, is reproduced from the magnetic tape while the signal is recorded on the magnetic tape, and a determining portion for determining abnormality of recorded signal based on the signal reproduced from the magnetic tape.
The determining portion determines the abnormality of recorded signal based on the fact whether or not a data format of at least a part of the signal reproduced from the magnetic tape is normal, and also determines malfunction of the heads based on a result obtained after comparing the signal reproduced from the magnetic tape with a reference signal.
The plurality of heads include a first recording/reproducing head and a second recording/reproducing head disposed on opposite outer surfaces of a head drum, and a third reproducing/reproducing head disposed on the outer surface the head drum and between the first and second recording/reproducing heads. Preferably, the first and second recording/reproducing heads are used to record/reproduce data in a standard definition (SD) mode for recording/reproducing, and the third reproducing/reproducing head is used in a standard definition long-play (SDL) mode of the recording/reproducing and not used in the standard definition (SD) mode.
According to the present invention, while the digital magnetic recorder/player performs recording, abnormality of recorded signal is detected by reproducing a signal from the magnetic tape just after the signal is recorded, and then inspecting the signal or comparing the signal with a reference signal. Also, especially when using the head, which is not used in a standard definition mode, for the purpose of detecting the abnormality of recorded signal, there is an advantage of not having to install an additional recording/reproducing head for detecting abnormality.
Meanwhile, according to the present invention, there is provided a method for detecting an abnormality of recorded signal of a digital magnetic recorder/player, including the steps of recording a signal on a magnetic tape, reproducing the signal from the magnetic tape, and determining abnormality of recorded signal based on the signal reproduced from the magnetic tape.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides an apparatus detecting abnormalities, said apparatus comprising: a plurality of heads recording data onto a medium and reproducing data from the medium; a controlling unit controlling said plurality of heads to reproduce a signal from the medium while the signal is being record ed onto the medium; and a determining unit determining an abnormality in the recorded signal in dependence upon the signal reproduced from the medium.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides a method for detecting an abnormality of a recorded signal, comprising the steps of: recording a signal on a medium; reproducing the signal from the medium; and determining an abnormality of the recorded signal in dependence upon the signal reproduced from the medium.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides an apparatus, comprising: a plurality of heads recording data onto a medium and reproducing data from the medium, said heads reproducing a signal from the medium while the signal is being recorded onto the medium; and a determining unit determining an abnormality in the recorded signal in dependence upon the signal reproduced from the medium.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides a recording and reproducing apparatus, comprising: a controller outputting first and second switching signals; a first switch operating in response to said first switching signal, said operating of said first switch activating a first head to record first data onto a medium; and a second switch operating in response to said second switching signal, said operating of said second switch activating a second head to reproduce second data from the medium, said second data corresponding to said first data recorded on the medium; said reproducing of said second data being performed during said recording of said first data.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides a recording and reproducing apparatus, comprising: a processor having an input terminal and an output terminal; said processor outputting a first data signal from said output terminal; and said processor receiving a second data signal at said input terminal during said outputting of said first data signal.
The present invention is more specifically described in the following paragraphs by reference to the drawings attached only by way of example. Other advantages and features will become apparent from the following description and from the claims.